TM 5-3895-374-10options . . utilities .................................................................................................................................. CALIBRATION display<8><6>The Calibration menu subscreen is shown in Figure 86.0. Note that this screen overlays the previous menu with thecontinuation options allowed for calibration and system configuration tasks.Some process control systems are calibrated with screwdriver, voltmeter, and stopwatch and leave the operator with nocertain knowledge of the exact settings for current or previous calibrations. This computer is calibrated through the keypadso that all calibrations are numeric values that can be printed and kept for reference. Consistency of values fromcalibration to calibration indicate system stability. Unauthorized changes to calibrations can quickly and certainly bedetermined by comparison with the printed and dated calibration record. For most cases, the entire computer could bereplaced and after installing the old calibration values would be in tolerance.The Continuation Options are:OPTIONKEYDESCRIPTIONESCapeESCReturn to the previous display.Alarm Limits2Display the screen containing the user selected alarm tolerances and the time for acontinuous out of tolerance condition to cause plant shutdown. From this screen allvalues can be edited.Time Delays3Display the screen containing the user measured process timing intervals. Eachtime interval is the time required for a material to reach the point of liquid asphaltaddition as measured from the point at which the material is controlled. From thisscreen all values can be edited.Meters5Display the screen containing the zero and span calibration values for all meters.From this screen all values can be edited. From this screen various computerassisted calibration procedures can be selected.Feeder Rates8Display the screen containing the span calibration values for the feeders. From this screen all values can be edited. From this screen various computer assistedcalibration procedures can be selected.page F - 54SYSTEMS Equipment Corp. 8/31/89Page (29)